Q3A 750 kVA, 11 kV/ 400 V with 5% impedance distribution transformer is to beinstalled in an industrial power network to serve the industrial motor pump asdepicted in Figure Q3.(1) Analyse the short circuit capacity of the transformer (in kVA)(1) Investigate the voltage variation (in percentage) during the motor starting(ii) Recommend a proper size of the transformer if the voltage variation duringthe motor starting is to be limited to a maximum value of 8%Infinite sourceStandard rating (in kVA):150, 250, 300, 400, 500,630, 750, 1,000, 1,250,1,600, 2,000, 2,500750 KVA11kv/ 400VHorse Power = 500 HPMPF=0.8 lagging, Efficiency = 70%Starting inrush current = 6 times

Given that : z=5% =0.05 1) short circuit capacity of transform Isc(pu)=1/z(p0)…

Q3 A 750 kVA, 11 kV/ 400 V with 5% impedance distribution transformer is to be installed in an industrial power network to serve the industrial motor pump as depicted in Figure Q3. (1) Analyse the short circuit capacity of the transformer (in kVA) (1) Investigate the voltage variation (in percentage) during the motor starting (i) Recommend a proper size of the transformer if the voltage variation during the motor starting is to be limited to a maximum value of 8% Infinite source Standard rating (in kVA): 150, 250, 300, 400, 500, 630, 750, 1,000, 1,250, 1,600, 2,000, 2,500 750 kVA 11kV/400V Horse Power = 500 HP MPF=0.8 lagging, Efficiency = 70% Starting inrush current = 6 times

Q3 A 750 kVA, 11 kV/ 400 V with 5% impedance distribution transformer is to be installed in an industrial power network to serve the industrial motor pump as depicted in Figure Q3. (1) Analyse the short circuit capacity of the transformer (in kVA) (1) Investigate the voltage variation (in percentage) during the motor starting (i) Recommend a proper size of the transformer if the voltage variation during the motor starting is to be limited to a maximum value of 8% Infinite source Standard rating (in kVA): 150, 250, 300, 400, 500, 630, 750, 1,000, 1,250, 1,600, 2,000, 2,500 750 kVA 11kV/400V Horse Power = 500 HP MPF=0.8 lagging, Efficiency = 70% Starting inrush current = 6 times

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.28MCQ

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